Esters of oxypkopylated



United States Patent *Ofiice 2,695,914 Patented Nov. 30, 1954 ESTERS F @XYPRQPYLATEDIVIONO GLYCEROL ETHERS AND PDLYCARBDXYLIC ACIDS Melvin De Groote, Louis, Mo assignor. to Petrolite Corporation, a corporation of Delaware No Drawing. Application January 9, 1952,

' Serial No. 265,705

Claims. (Cl. 260-475) The present invention is concernedwith certain new chemical products, compounds or compositions which have useful application in various arts. 1

The particular compounds subsequently described herein in greater detail are hydrophile synthetic products,

and more particularly, fractional esters obtained from polycarboxy acids and diols obtainedby the oxypropylation of dihydroxylated ethers of glycerol with the proviso .that the ether radical have less than 8 carbon atoms and is preferably obtained from a water-soluble aliphatic alcohol. Glycerol ethers which are available for this type of synthesis include glycerol alpha-allyl ether,

glycerol alpha-ethyl ether, glycerol alpha-isopropyl ether,

etc. .As an example of a suitable reactant reference is made specifically to glycerol alpha-isopropyl ether.

Momentarily ignoring certain variants of structure which -will be considered subsequently the demulsifier maybe proviso that n plus n equals a sum varying from to 80; n is a-whole number not over 2 and R is the radical v of the polycarboxy radical COOH and preferably free from any radicals having more than 8 uninterrupted carbon atoms in a single group, and with the further proviso that the parent diol prior to esterification be water-insoluble and kerosene-soluble.

The products. of this invention are of particular value for resolving petroleum emulsions of the water-in-oil type that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil Which constitutes the continuous phaseof the emulsion. This use of the particular products described herein is ;described and claimed in my copending application Serial No. 179,400, filed August 14,1950, now abandoned.

The products are also useful for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude .oil. and relatively soft waters or weak ,brines. Controlled emulsification and subsequent demulsification underthe conditions just mentioned are of significant value in removing. impurities particularly inorganic salts from pipeline oil.

As previously stated it is my preference to employ derivatives in which the ether group is supplied by an aliphatic alcohol, preferably having at least 3 carbon atoms and being water-soluble, such as propyl alcohol, butyl alcohol, or amyl alcohol. amyl alcohols some of the isomers are water-soluble to the extent that they show solubility of at least a few per cent at room temperature. Such ethers can be prepared in various ways and one of the simplest procedures involves the treatment of an 'alcohol with a mole of In the case of butyl or glycide. Other procedures involve a similar reaction in which the alcohol is treated with epichlorohydrin under conditions so a substituted ethylene or propylene oxide is obtained, i. e., a compound having an epoxy ring which is then reacted with Water to yield the corresponding glycerol ether. Such intermediates containing the epoxy ring are sometimes referred to as glycidyl ethers.

As to patents that illustrate such procedure see U. S. Patents Nos. 1,959,930, 2,089,569, 2,164,007, 2,181,100, 2,221,818, 2,258,892, 2,314,039, 2,380,185, 2,453,634, 2,413,860, 2,010,726, and British Patent No. 518,057.

See also pamphlet entitled Epichlorohydrin, issued by ihell Chemical Corporation, New York city, New Yor For convenience, what is said hereinafter will be divided into four parts:

Part 1 is concerned with the preparation of the oxypropylation derivatives of the glycerol ether type of diol; Part 2 is concerned with the preparation of the esters from the oxypropylated derivative;

-Part 3 is concerned ,with a consideration of the structure of the glycerol ether type of diols which is of significance in light of what is said subsequently; and

Part 4 is concerned with certain derivatives which can be obtained from the oxypropylated diols. In some instances, such derivatives are obtained by modest oxyethylation preceding the oxypropylation step, or oxypropylation followed by oxyethylation. This results in diols having somewhat different properties which can then be reacted with the same polycarboxy acids or anhydrides described in Part 2.

PART 1 Oxypropylation, like other oxyalkylation operations, should be carried out with due care, in equipment specially designed for the purpose and with precautions that are now reasonably Well understood. Reference is made to the discussion of the factors involved in oxypropylation which appears in Patent 2,626,918, column 5 through column 8, the considerations and the technique there discussed being equally applicable to the production of the compounds of the present application. In view of this reference to Patent 2,626,918, no general discussion of the factors involved in oxypropylation is given here, and the procedure will simply be illustrated by the following examples:

Example 1a The particular autoclave employed was one with a capacity of approximately 15 gallons, or on the average of about pounds of reaction mass. The speed of the stirrer could be varied from to 350 R. P. M. 8 /2 pounds of glycerol alpha isopropyl ether were charged into the autoclave along with one pound of sodium hydroxide. The reaction pot was flushed out with nitro gen. The autoclave was sealed, the automatic devices adjusted and set for injecting a total of 58 pounds of propylene oxide in approximately a 5-hour period. The

. pressure regulator was set for a maximum of 35 pounds initial introduction of propylene oxide was not started until the heating devices had ralsed the temperature to approximatelytthe boiling point of water. At the completion of the reaction a sample was taken and oxypropylation proceeded as in Example 2a, immediately succeeding.

Example 2a 59.5 pounds of the reaction mass identified as Example 1a, preceding, were permitted to remain in the reaction vessel and withoutthe addition of any more catalyst 43 pounds of propylene oxide were added. The oxypropylation was conducted in substantially the same manner in regard to. pressure and temperature as in Example 1a,

preceding, except that the reaction was complete in slightly less time, i. e., 4 hours instead of hours. At the end of the reaction period part of the sample was Withdrawn and Oxypropylation was continued as described in Example 3a, following.

Example 3:!

Approximately 68 pounds of the reaction mass identified as Example 20, preceding, were permitted to remain in the reaction vessel. Slightly more than 27 pounds of propylene oxide were introduced during this period. No additional catalyst was added. The conditions of reaction as far as temperature and pressure were concerned were substantially the same as in Example 1a, preceding. The reaction time was the same as in Example la and a 1 little more than in Example 2a, i. e., 5 hours. At the a completion of the reaction part of the reaction mass was withdrawn and the remainder subjected to Oxypropylation as described in Example 4a, succeeding.

Example 4a Slightly over 70 pounds of the reaction mass identified as Example 3a, preceding, were permitted to remain in the autoclave. No additional catalyst was introduced. Slightly over 15.5 pounds of propylene oxide were intro- 2 duced in the same manner as described in Example In, preceding. Conditions in regard to temperature and pressure were substantially the same. In this instance the oxide was introduced in slightly less than 6 hours. At the end of the reaction period part of the sample was withdrawn and the remainder of the reaction mass subjected to further Oxypropylation as described in Example 5a, succeeding.

Example 5a Approximately 60 pounds of the reaction mass identified as Example 4a, preceding, were permitted to remain in the autoclave. No additional catalyst was introduced. Slightly over 36.5 pounds of propylene oxide were added. The conditions of temperature and pressure were substantially the same as preceding. Note, however, that due to further dilution of catalyst approximately twice as long was required as in previous oxypropylations, i. e., 10 hours. Oxypropylation was continued as described in Example 6a, succeeding.

Example 6a Approximately 68 pounds of reaction mass identified as Example 50, preceding, were permitted to stay in the autoclave. This was subjected to reaction with slightly under 26 pounds of propylene oxide. Conditions of reaction were substantially the same as described in EX- ample 10 as far as temperature and pressure were concerned. The period required for the addition of the oxide was 8 hours.

What has been said herein is presented in tabular form in Table 1 immediately following, with some added information as to molecular weight and as to solubility of the reaction product in water, xylene and kerosene.

residual caustic soda employed. This would also be the case if sodium methylate were used as a catalyst.

Speaking of insolubility in water or solubility in kerosene, such solubility test can be made simply by shaking small amounts of the materials in a test tube with water, for instance, using 1% to 5% approximately based on the amount of the water present.

Needless to say, there is no complete conversion of propylene oxide into the desired hydroxylated compounds. This is indicated by the fact that the theoretical molecular weight based on a statistical average is greater than the molecular weight calculated by usual methods on basis of acetyl or hydroxyl value. Actually, there is no completely satisfactory method for determining molecular weights of these types of compounds with a high degree of accuracy when the molecular weights exceed 2,000. In some instances the acetyl value or hydroxyl value serves as satisfactorily as an index to the molecular weight as any other procedure, subject to the above limitations, and especially in the higher molecular weight range. If any difiiculty is encountered in the manufacture of the esters as described in Part 2 the stoichiometrical amount of acid or acid compound should be taken which corresponds to the indicated acetyl or hydroxyl value. This matter has been discussed in the literature and is a matter of common knowledge and requires no further elaboration. In fact, it is illustrated by some of the examples appearing in the patent previously mentioned.

Using a smaller autoclave, i. e., one having a capacity slightly less than one gallon, I have prepared a number of similar compounds from glycerol alpha butanol ether obtained by reacting normal butanol with glycerol, and also from glycerol alpha pentanol-3 ether obtained by reacting pentanol-3 with glycide. These others were oxypropylated in substantially the same manner and under substantially the same conditions as Examples 1a through 6a, preceding. For sake of brevity the data are sum marized in the following table:

TABLE 2 Molecular Ex. No. Reaetant u r hydroxyl weight fii 7a Glycerol alpha butanol ether 1,008 730 8a v.110 1,907 1,200 3, 000 1, 303 3, 602 1,372 4, 738 1,707 5, 666 1, 919 1.120 784 2, 057 1, 278 3, 144 1, 340 3, 950 1, 470 4, 600 1, 756 5, 517 1,870

The above products were comparable in physical appearance although in some instances somewhat darker than those derived from the isopropyl ether.

TABLE 1 Composition before Composition at end tMax. Maxi.b Tie Ex. No. y eemp., pres, s.

H. C." Oxide Theo. H. C.* Oxide hrs.

mm" Cafiaglyst, amt, amt oaltgaslyst, termm. F. sq. in.

lbs. lbs I wt. lbs. lbs.

The hydroxylated compound is glycerol alpha isopropyl ether.

products were, of course, slightly alkaline due to the 85 Restating the type of compound herein specified one need only rewrite the first formula above in which the isopropyl group is replaced by the radical R, thus:

purpose.

'Only a trace of acid need be present.

which "all the various characters jhave"theinprevious isomers in which the ether radical is in the beta position can be prepared and are just as'sati'sfactory but the' cost of preparation does not justify their use for thepresent They are, of coursejthe obvious'e'qulvale'nts.

PART 2 As previously 'pointed out the present invention; is concerned with acidic esters obtained from the oxypropylated derivatives describe'din'Part 1. immediately preceding,

and polycarboxy'acids, particularly dicarboxy acids such as adipic acid, phthalic'acid, or'anhydride, succlmc acid,

diglycollic acid, sebacic acid, azelaic'acid, aconitic acid,

includes the anhydrides' or any other-obvious equiva- 2 My preference, however, is to use polycarboxy lents. acids having not over 8 carbon atoms.

The production of esters including'acid esters (fractional esters) from pblycarboxy acids and "glycols or other hydroxylated compounds is well known. Needless to say, various compounds maybe used such as the low molal ester, the anhydride, the acyl chloride, etc. However, for purpose of economy it is customary to use either the acid or the anhydride. Aconventionali procedure is employed. On a laboratory scale one can emloy a resin pot of the'kind described in U. S. Patent No. 2,499,370, dated March 7, '1950, to De'Groote and Keiser, and particularly with one more opening to permit the use of a porous spreader if hydrochloric acid gas is to be used as a catalyst. Such device or absorption spreader consists of minute alundum thirnbles which are'connected to a glass tube. One can add a sulfonic' acid such as 'p'aratoluene sulfonic acid as a catalyst. There-is some objection to this because in some instances there is some evidence that this acid catalyst tends to decompose orrearrange oxypropylated compounds, and particularly likely to do so if the esterification temperature 'is'too h'i'gh. In the case of polycarboxy acids such as digly'collic acid, which is strongly acidic there is no need to' add any catalyst. The use of hydrochloric gas has one advantage over para-toluene sulfonic acid andthat -is-that atthe end of the reaction it can be removed by flushing outwith nitrogen, whereas there is no reasonably convenient means available of removing the para-toluene, sulfonic acid or other sulfonic acid employed. -If hydrochloric acid is employed one need only pass the gas through at anexceedin'gly slow rate so as to keep the reaction mass-acidic. I have employed hydrochloric acid gas or the aqueous acid itself to 'eliminate the initial basic material. My preference, however, is to use no catalyst whatsoever and to :insure complete dryness of the diol as described in the final procedure just preceding Table 3.

. The products obtained in Part 1- preceding maycontain a basic catalyst. As a general procedure I-have added an amount of half-concentrated hydrochloric acid considerably in excess of what is required to neutralize the residual catalyst. The mixture is shaken thoroughly and allowed to'stand overnight. It is then filteredand refluxed; with I sodium chloride during the reflux stage needless to say a second filtration may be-required. In any event the neutral or slightly acidic solution of the oxypropylated derivatives described in Part 1 is then diluted further with suflicient xylene, decalin, petroleum, 'solvent,.'or the like, sothat one has obtained approximately a 45% 'solution. "To this solution there is added a'polycarboxy1ated"re-' actant as previously described, suchas' phthal'ic afiliyd'ride, succinic acid or an'hyd'ride,-'diglycollic -acid, ew. The mixture is refluxed until esterification is comple'te as indicated by elimination of water or drop in-earboxyrvalue. Needless to say, if one produces a half e'ster from -an-anhydride such as phthalicanhydride, no "water is 'eli'minated. However, if it is obtained from diglycollic acid, for example, water is eliminated. All such-p-rocedures are conventional and have been so thoroughly 'describe'd in the literature that further consideration "will be lim'ite'd to a few examples and a comprehensive table.

Other procedures-foreliminating the basic ;residual catalyst, if any, can be employed. 'For exarnp'le,; the oxyalkylation can be conductedin absence of a-'solve'nt-or the solvent removeda'fter oxypropylation. Such oxypropylation end product can then be-acidified withjust enough concentrated hydrochloric acidtojust neutralize the residual basic catalyst. To this "product "one canthen add a small amount of anhydrous sodium sulfate (sufficient in quantity to take upany water that' ispresent) and then subject the mass to centrifugal force-so as to eliminate the hydrated sodium sulfate and probably the sodium chloride formed. The clear somewhat viscous straw-colored amber liquid so obtained may contain a small amount of sodium sulfate or sodium chloridebut, in any event, is perfectly acceptable for esterification in the manner described.

It is to be pointed out that the products here described are not polyesters in the sense that there is a plurality of both diol radicals and acid radicals; the product is characterized by'having only one diol radical.

In some instances and, in fact, in many instances I have found that in spite of the dehydration methods employed above that a mere trace of water still comes through and that this mere trace of water certainly interferes with the acetyl or hydroxyl value determination, at least when a number of conventional procedures are used and may retard esterification, particularly where there is no sulfonic acid or hydrochloric acid present as-a catalyst. Therefore, I have preferred to use the following procedure: I have employed about 200 grams'of the diol as descrlbed in Part 1, preceding; I have added about grams of benzene, and then refluxed this mixture in the glass resin pot using a phase-separating trap until the benzene carried out all the water present as'water ofsolution or'the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of l30to possibly 150 C. When all this water or moisture has been removed I also withdraw approximately 20 grams or a little less benzene and then add'the required amount of-the carboxy reactant and also about 150 grams of a'hi'gh boiling aromatic petroleum solvent. These solvents are sold by various oil refineries and, as far as solvent'effect act as if they were almost complete aromatic in eharacter. Typical distillation data in the particular type I have employed and found very satisfactory is the following:

I. B. P., 142 C. '50 ml., 242 C.

5 ml., 200 C. 55 ml., 244 C. 10 ml., 209 C. '60 ml., 248 C. 15 ml., 215 C. ml., 252 C. 20 ml., 216 C. ml., 252 C. 25 ml., 220 C. ml., 260 C. 30 ml., 225 C. -ml., 264 -C. 35 ml., 230 C. ml., 270 C. 40 ml., 234 C. ml., 280 C. 45 ml., 237 C. ml., 307 C.

After this material is added, refluxing is continued and,

above about 200 C.

The use of such solvent is extremely satisfactory provided one does not attempt to remove the solvent subsequently except by vacuum distillation and provided there is no objection to a little residue. Actually, when these materials are used for a purpose such as demulsification the solvent might just as well'be allowed to remain. If the solvent is to be removedby distillation, and'particularly vacuum distillation, then the high boiling aromatic petroleum solvent might well be replaced by some more expensive solvent, such as decalin or an alkylated decalin which has a rather definite or close range boiling point.

The procedure for manufacturing the esters has been illustrated by preceding examples. If for any reason reaction does not take place in a manner that is acceptable, attention should be directed to the following details:

The removal of the solvent, of course, is purely a con- (a) Recheck the hydroxyl or acetyl value of the oxyproventional procedure and requires no elaboration. pylated glycerol ether and use a stoichiometrically equiv- In the appended table Solvent #7-3, which appears n alent amount of acid; (b) if the reaction does not proceed all instances, is a mixture of 7 volumes of the aromatic with reasonable speed either raise the temperature indipetroleum solvent previously descr bed and} volumes of cated or else extend the period of time up to 12 or 16 benzene. This was used, or a similar mixture, m th e hours f need be; (c) if necessary, use of paratoluene manner prev10usly described. In a large number of simisulfonic acid or some other acid as a catalyst; (d) if the lar examples decalin has been used but it is my preference esterification does not produce a clear product a check to use the above mentioned mixture and particularly with should be made to see if an inorganic salt such as sodium the preliminary step of removing all the water. If one chloride or sodiumsulfate is not precipitating out. Such does not intend to remove the solvent my preference salt should be eliminated, at least for exploration experiis to use the petroleum solvent-benzene mixture although mentat on, and can be removed by filtering. Everything obviously any of the other mixtures, such as decalin and else being equal as the size of the molecule increases the xylene, can be employed. reactive hydroxyl radical represents a smaller fraction The data included in the subsequent tables, 1. e., Tables of the entire molecule and thus more dlfiiculty is involved 3 and 4, are self-explanatory, and very complete and in obtaining complete esterification. it is believed no further elaboration is necessary. Even under the most carefully controlled conditions of TABLE 3 Theo M01. wt. A mt. of Amt. of Ex. N0. Ex. N0. Theo. Actual of acid of oxy M. W. of hygmxyl hydroxyl 2223 3 3 86 Polycarboxy reactant gg gzg ester cmpd. H. 0. EL 0 value H. V (GS) tam (gs) 1, 043 107 159 704 194 Diglycollic mm. 73.5 1, 048 107 159 704 194 81. 5 1, 043 107 159 704 194 54. 0 1,048 107 159 704 194 Aconltic acid 95.0 1, 048 107 159 704 194 Citraconic anhydri 63. 5 1,043 107 159 704 194 --..do 53.5 1,314 51.7 104 1,075 195 Diglycollic ac1d 49.0 1,814 51.7 104 1,075 195 Phthalic anhydride 54.0 1, 814 61. 7 104 1, 075 195 Maleic anhydride 35. 7 1, 814 61. 7 104 1, 075 195 Aconitic acld 63. 3 1, 814 61. 7 104 1, 075 195 Citraconic acid 40. 7 2,550 43.7 84.9 1,320 202 Diglycollic acid 41.0 2,550 43.7 84.9 1,320 202 Phthalie anhydride... 45.3 2,550 43.7 94.9 1,320 207 Maleic anhydrlde 30.8 2,550 43.7 84.9 1,320 200 Aconitic acid 54.3 2, 550 43.7 84.9 1,320 197 Oitraconic anhydride 34.0 3,125 35.9 57.9 1,550 197 Diglycollic acid 31.9 3,125 35.9 57.9 1,550 197 Phthalic anhydride 35.2 8, 125 35. 9 67. 9 1, 650 199 Maleic anhydride 23. 5 3,125 35.9 57.9 1,550 201 Aconitic acid 42.5 3, 125 35. 9 67. 9 1, 650 198 Oitraconic anhydride 2G. 6 3, 125 35. 9 67. 9 1, 650 200 Methylene disalieylic. 69. 1 5,050 22.1 53.2 1, 925 200 Diglycollic acid 27.0 5, 050 22.1 58.2 1,925 197 Phthalic auhydride... 30.2 5, 050 22. 1 58. 2 1, 925 197 Maleic anhydride 20.0 5,050 22.1 58.2 1,925 198 Aconitic acid 35.3 5, 050 22.1 58.2 1, 925 198 Citraconic anhydride.. 23.0 5,945 15.3 51.4 2,170 195 Diglycollic acid 25.2 5,945 15.3 51.4 2,170 195 Phthalic anhydride-.- 27.0 6, 945 10. 3 51. 4 2, 170 196 Maleic acid 17. 7 5,945 15.3 51.4 2,170 195 Aconitic acid 31.5 5,945 15.3 51.4 2,170 204 O1tracon1canhydride 20.3

*Sample decomposed somewhat; discarded.

TABLE 4 oxypropylation involving comparatively low temperatures and long time of reaction there are formed certain com- Esterifica- Time of pounds whose composition is still obscure. Such side v W g Solvent 2 g s t pq testerilfica- 22%? reaction products can contribute a substantial proportion mn of the final cogeneric reaction mixture. Various suggestions have been made as to the nature of these com- 258 fig 5 pounds, such as being cyclic polymers of propylene oxide, fig 313 151 dehydration products with the appearance of a vinyl radi- 23g 155 3% 9 g cal, or isomers of propylene oxide or derivatives thereof, #7-3 253 219 1 on 1. e., of an aldehyde, ketone, or allyl alcohol. In some fig 323 18g 5 kg instances an attempt to react the stoichiometric amount 250 160 5 of a polycarboxy acid with the oxypropylated derivative #z-s 232 154 2 None results in an excess of the carboxylated reactant for the gig g g g reason that apparently under conditions of reaction less 237 152 5% 8 reactive hydroxyl radicals are present than indicated by the #7-3 247 143 5% None hydroxyl value. Under such circumstances there is sim- Zkg ii: 33 3 2 ply a residue of the carboxylic reactant which can be re- 234 146 moved by filtration or, if desired, the esterification pro- 433 224 153 4% 4.4 cedure can be repeated using an appropriately reduced 234 9 None ratio of carboxylic reactant. #7-3 223 150 5 None 240 172 5% Even the determination of the hydroxyl value and con- #7-3 223 147 3% 0.4 ventional procedure leaves much to be desired due either 2kg 3% g g? to the cogeneric materials previously referred to, or for 225 153 5 None that matter, the presence of any inorganic salts or pro- #7-3 220 140 5 None pylene oxide. Obviously this oxide should be eliminated. #7-3 230 185 7% 3.4 223 154 4% None The solvent employed, if any, can be removed from 237-3 218 155 3% 3.1 the finished ester by distillation and particularly vacuum 3kg 13g 2% 1x3: distillation. The final products or liquids are generally 225 181 4% 3, 2 pale amber to amber in color, and show moderate viscos- #7-3 224 153 4% None ity. They can be bleached with bleaching clays, filtering chars, and the hke. However, for the purpose of demulsifi c ationor thelikecolonis notafactor anddecolorization is lnot'ijus'tified. i

In the above instances i have. pj rmittedthe solvents, to remain present in the. final reaction mass. In other instances l have followed the 'same procedure using'decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vacuum distillation. Appearances of the final products are much the same as th e. diols before esterification andin some instances were somewhat darker incolor andhad a reddishcast'and perhaps somewhat. more viscous,

PAR 3 Previous reference has been made to the fact that diols such as polypropyleneglycol of approximately 2,000 molecular weight, for example, have been esterified with di carboxy acids and employed as demulsifying agents. On first examination the difference between the herein described products and such comparable products appears to be rather insignificant. In fact, the difference is such that it failsto explain the fact that compounds of the kind herein described m be, andrrequenny are, 10%, or better on a quantitative basis than the simpler compound previously described, and demulsifyfa'ster and give cleaner oil in many instanc'es'. The method of making such comparative tests has been described in a bo'okletentitled Treating Oil Field 'Emulsions,- used in the Vocational Trainin'g'"Course,Petroleum Industry Series, of the American Petroleum Institute,

The difference of course, does not reside in the carboxy acid but in the diol. Momentarily an effort will be made to emphasize certain things in regard to the structure ofapol ypropylenefglycol, such as polypropylene glycol of af20'00jrnolecular weight. Propyleneglycolhas a primary alcohol radical and as'econdar'y' alcohol radical." In this sense the building unit which forms polypropylene glycols is not symmetrical. Obviously, then, polypropylene glycols can be obtained, at least theoretically, in which two secondary alcohol groups are united or a secondary a1 cohol group'is united to a primaryalcohol group, etherization being involved, of course, in each instance.

Usually no effort is made to'differentiat'e between oxypropylation takingplace, for example, at the primary alcohol unit radical or the secondary alcohol radical. Actually, when such products are'obtained,"such as a high molal polypropylene glycol or the products'obt'aine'd in the manner herein described one does 'not obtain a single derivative such as HO(RO)nI -I' in which n'fhas one'and only one'v'alue, forinstance 14, 15 or 16, or the like. Rathen'oneobtains a cogeneric mixture of closely related or touching homologues." These materialsinvariably have high molecular weights and cannot be separated from one anotherby' any known procedurefwi'thout decomposition. The properties of such mixture representthecohtribution of the various individual members of the mixture. On a statistical Basis, "ofcourse, ncan be appropriately specified.

In the instant. situation it becomes obvious that if an ordinary high molal propyleneglycol is compared to strings of white beads of various lengths, the diols herein employedf'as intermediates are characterized by the presence of a black bead, i. e., a radical which corresponds to a dihydroxylated glycerol ether as previously described, that is, for example the radical Furthermore, it becomes obvious that one now has a nonsymmetrical radical in the majority of cases for the reason that in the cogeneric mixture going back to the corresponding formula n and n are usuallynot equal. For instance, if one introduces 15 moles of propylene oxide, rz andn could not be equal, insofar that the nearest approach to equality'is where the value n is 7 and rt is 8 However, evenin the case of an even number'such as 20, 30, 40 or 50, it is also obvious that n andn' will not be equal in light of what has been said previously. Both sides of, the molecule are not going to grow with equal rapidity, i. e.,"to the same size. Thus the diol herein'employed is differentiated from polypropylene diol 2000, for example, in that (a) it carries a hetero unit, il e., a unitother than apropylene glycol or propylene oxide unit, (b) such unit is oif center, and (c) the effect of. that unit, offcourse, must have some effect in the range with which the linear molecules can be drawn together by hydrogen binding or van der Waals forces, or whatever elsemay be involved.

'What has'been said previously can be emphasized in the following manner. It has been pointed out previouslytha't in the last formula immediately preceding '11 or n could be zero. Under the conditions ofma'nufacture as described in Part 1 it is extremely unlikely that I is ever zero. However, such compounds can'be prepared readily with comparatively little difli'c'ulty by resorting to "a blocking effect or reaction. For instance, if the dihydroxylated glycerol ether isesterified with a low molal acid. such as acetic acid mole for mole and such product sub jected to oxyalkylation using a catalyst, such as sodium methylate and guarding against the presence of any Water, it becomes evident that all thepropylene oxide introduced, for instance 15 to 80 molecules per polyhydric alcohol molecule necessarily must enter at one side only. If such product is then saponified so as to decompose the acetic acid ester and then acidified so as to liberate the watersoluble acetic acid and the water-insoluble diol asefparation can be made and such diol then subjected to esterifi cation as described in Part 2, preceding. Such esters, of course, actually represent products 'whereeither'n or n is zero. Also intermediate procedures can be employed, i. e., following'the same esterification step after partial. oxypropylation. For instance, onemight oxypropylate with one-half the ultimate amount of propylene oxide to be used and then stop the reaction. One could then convert this partial oxypropylated intermediate into an ester by reaction of one mole of acetic acid with one mole of a diol. This ester could then be oxypropylated with all the remaining propylene oxide, The final product so ob tained could be saponified and acidified so as to eliminate the water-soluble acetic acid and free the obviously un symmetrical 'diol which, incidentally, should/also bekerosene-soluble.

From a practical standpoint I have found no advantage in going to this extra step but it does emphasize the difference in structure between the herein described diols employed as intermediates andfhigh molal polypropylene glycol, such as polypropyleneglycol 2000.

PART 4 Previous reference has been made to other oxyalkylating agents other than propylene oxide, such as ethylene oxide. Obviously variants can be prepared which do not depart from what is said herein "but do produce modifications. The diol derived by etherization of glycerol in the manner described can be reacted with ethylene oxide in modest amounts and then subjected to oxypropylation provided that the resultant derivative is (a) water-insoluble, (b) kerosene-soluble, and (c) has present 15 to 80 alkylene oxide radicals. Needless to say, in order to have water-insolubility and kerosene-solubility the large majority must be propylene oxide. Other variants suggest themselves as, for example, replacing propylene oxide by butylene oxide.

More specifically then one mole of such etherized glycerol of the kind described can be treated with 2, 4 or 6 moles of ethylene oxide and then treated with propylene oxide so as to produce a water-insoluble, kerosene-soluble diol in which there are present 15 to 80 oxide radicals as previously specified. Similarly the propylene oxide can be added first and then the ethylene oxide, or random oxyalkylation can be employed using a mixture of the two oxides. The compounds so obtained are readily esterified in the same manner as described in Part 2, preceding. Incidentally, the diols described in Part 1 or the modifications described therein can be treated with various reactants such as glycide, epichlorohydrin, dimethyl sulfate, sulfuric acid, maleic anhydride, ethylene imine, etc.

If treated with epichlorohydrin or monochloroacetic acid the resultant product can be further reacted with a tertiary amine such as pyridine, or the like, to give quaternary ammonium compounds. If treated with maleic anhydride to give a total ester the resultant can be treated with sodium bisulfite to yield a sulfosuccinate. Sulfo groups can be introduced also by means of a sulfating agent as previously suggested, or by treating the chloroacetic acid resultant with sodium sulfite.

I have found that if such hydroxylated compound or compounds are reacted further so as to produce entirely new derivatives, such new derivatives have the properties of the original hydroxylated compound insofar that they are elfective and valuable demulsifying agents for resolution of water-in-oil emulsions as found in the petroleum industry, as break inducers in doctor treatment of sour crude, etc.

This application is a continuation-in-part of my copegding application Serial No. 179,400, filed August 14, 19 0.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula in which n and n are numerals including 0 with the proviso that 11 plus n equals a sum varying from 15 to 80, and n" is a whole number not over 2, R is an alkyl radical having less than 8 carbon atoms, and R is a radical of a polycarboxy acid selected from the class consisting of acyclic and isocyclic polycarboxy acids having not more than 8 carbon atoms and composed of carbon, hydrogen and oxygen of the formula:

OOOH

in which n" has its previous significance; and with the further proviso that the parent diol prior to esterification be water-insoluble and kerosene-soluble.

2. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula in which n and n are numerals excluding 0 with the proviso that n plus n equals a sum varying from 15 to 80, and n" is a whole number not over 2, R is an alkyl radical having less than 8 carbon atoms, and R is a radical of a polycarboxy acid selected from the class consisting of acyclic and is'ocyclic polycarboxy acids having not more than 8 carbon atoms and composed of carbon, hydrogen and oxygen of the formula:

COOH

(COOHL-II in which n" has its previous significance; and with the further proviso that the parent diol prior to esterification be water-insoluble and kerosene-soluble.

3. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula in which n and n are numerals excluding 0 with the proviso that n plus n equals a sum varying from 15 to 80; R is an alkyl radical having less than 8 carbon atoms, and R is a radical of a dicarboxy acid selected from the class consisting of acyclic and isocyclic dicarboxy acids having not more than 8 carbon atoms and composed of carbon, hydrogen and oxygen of the formula:

COOH

COOH

and with the further proviso that the parent diol prior to esterification be water-insoluble and kerosene-soluble.

4. The product of claim 3 wherein R has at least 3 carbon atoms.

5. The product of claim 3 wherein R has at least 3 carbon atoms and is derived from a water-soluble alcohol.

6. The product of claim 3 wherein R has at least 3 carbon atoms, is derived from a water-soluble alcohol, and the dicarboxy acid is phthalic acid.

7. The product of claim 3 wherein R has at least 3 carbon atoms, is derived from a water-soluble alcohol, and the dicarboxy acid is maleic acid.

8. The product of claim 3 wherein R has at least 3 carbon atoms, is derived from a water-soluble alcohol, and the dicarboxy acid succinic acid.

9. The product of claim 3 wherein R has at least 3 carbon atoms, is derived from a water-soluble alcohol, and the dicarboxy acid is citraconic acid.

10. The product of claim 3 wherein R has at least 3 carbon atoms, is derived from a water-soluble alcohol, and the dicarboxy acid is diglycollic acid.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,507,560 De Groote May 16, 1950 2,562,878 Blair Aug. 7, I951 

1. HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING CHARACTERIZED BY THE FOLLOWING FORMULA 